Design : Prospective, randomized, single-center clinical trial Setting : mixed medical-surgical 45 bed ICU in a tertiary university hospital Patients : 250 patients with Acute Kidney Injury (AKI) stage III needing renal replacement therapy Interventions : Patients are randomized to receive SLEDD using standard dialysate and systemic anticoagulation with UF versus SLEDD using Citrasate®-dialysate with no additional UF.